From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp02.citrix.com ([66.165.176.63]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1SphDW-0005Qs-QV for kexec@lists.infradead.org; Fri, 13 Jul 2012 14:51:40 +0000 Message-ID: <500035EB.1020502@citrix.com> Date: Fri, 13 Jul 2012 15:51:23 +0100 From: Andrew Cooper MIME-Version: 1.0 Subject: Re: [Xen-devel] [PATCH 1/5] xen: Always calculate max_cpus value References: <20120705145839.GB2007@host-192-168-1-59.local.net-space.pl> <20120705150008.GC2007@host-192-168-1-59.local.net-space.pl> <4FF5D557020000780008DEA5@nat28.tlf.novell.com> <20120713131907.GB1876@host-192-168-1-59.local.net-space.pl> In-Reply-To: <20120713131907.GB1876@host-192-168-1-59.local.net-space.pl> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Daniel Kiper Cc: "olaf@aepfle.de" , "konrad.wilk@oracle.com" , "kexec@lists.infradead.org" , xen-devel , "anderson@redhat.com" , Jan Beulich , "crash-utility@redhat.com" On 13/07/12 14:19, Daniel Kiper wrote: > On Thu, Jul 05, 2012 at 04:56:39PM +0100, Jan Beulich wrote: >>>>> On 05.07.12 at 17:00, Daniel Kiper wrote: >>> max_cpus is not available since 20374 changeset (Miscellaneous data >>> placement adjustments). It was moved to __initdata section. This section >>> is freed after Xen initialization. Assume that max_cpus is always >>> equal to XEN_HYPER_SIZE(cpumask_t) * 8. >> Using nr_cpu_ids, when available, would seem a better fit. And > Hmmm... I could not find such animal in Xen source code. > However, maybe I missed something. nr_cpu_ids was introduced into xen-unstable with c/s 23982:511d5e65a302 It is not present in 4.1 or earlier. ~Andrew > >> I donm't see why, on dumps from old hypervisors, you wouldn't >> want to continue using max_cpus. Oh, wait, I see - you would >> have to be able to tell whether it actually sits in .init.data, which >> might not be strait forward. > Yep, but I will try to improve that once again. > > Daniel -- Andrew Cooper - Dom0 Kernel Engineer, Citrix XenServer T: +44 (0)1223 225 900, http://www.citrix.com _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec